Conductor sleeve and packing gland for sub-aqueous marine drilling



May 4, 1965 Filed May 20, 1965 W. P- VERVILLE CONDUCTOR SLEEVE AND PACKING GLAND FOR SUB-AQUEOUS MARINE DRILLING 3 Sheets-Sheet l INVENTOR. I W|LL| M D, VEQV\L LE BY Q.

A-r-ro NEV May 4, 1965 W. P. VERVILLE CONDUCTOR SLEEVE AND PACKING GLAND FOR Filed May 20, 1963 SUB-AQUEOUS MARINE DRILLING 3 Sheets-Sheet 2 HIGH "nos.

AN H "u!" OCEAN FLOOR ANCHOR LME,

INVENTOR. W\L.L.\AM P. VEQVH-LE.

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AT-roCzNEy May 4, 1965 w. P. VERVILLE 3,181,628

CONDUCTOR SLEEVE AND PACKING GLAND FOR SUB-AQUEOUS MARINE DRILLING Filed May 20, 1963 3 Sheets-Sheet 3 ATToQNEy United States Patent 3,181,628 CONDUCTOR SLEEVE AND PACKING GLAND FOR SUB-AQUEOUS MARINE DRILLING William P. Verville, Rte. 2, Concord, NH. Filed May 20, 1963, Ser. No. 281,846 4 (,laims. (Cl. 175-19) (Granted under Title 35, US. Code (1952), see. 266) The invention described herein may be manufactured and used by or for the Government for governmental purposes without the payment to me of any royalty thereon.

This invention relates to a novel apparatus for drilling below the surface of rough or choppy water due to tidal fluctuations, ground swells or wash caused by passing vessels and the like.

Formerly, the problem of adding and taking off drill casing to compensate for tidal fluctuations was usually performed in the drilling industry by the erection of large tubular steel scaffolds and towers, driving piling and erecting a work platform on the piling above high tide, elaborate hydraulically operated elevators mounted on a floatin-g plant, large diameter caissons guyed to the floating plant, and the use of large spudded craft. The high cost of constructing and maintaining this special equipment and the cost of transporting and modifying it for each site makes the use of such equipment generally prohibitive.

More recently, .the above problems 'have been partially solved by a less expensive and practical method of performing sub-aqueous drilling through a specially constructed well in the hull of the floating plant or off a cantilever drill platform erected on the bow of the craft. The two daily tide changes of as much as 30 feet in some localities, however, requires a drill crew to constantly add or take off drill casing to adjust for the tidal changes when operating off a floating plant. This procedure interrupts drilling operations, makes conventional drive sampling or undisturbed sampling with the use of drilling mud most difficult and reduces drastically actual productive drilling time and certainly leaves much to be desired.

This new apparatus for performing sub-aqueous drilling solves the above problems in a large measure by using a conductor sleeve and packing gland which eliminates the problem of adding and taking off drill casing to compensate for tidal fluctuations and makes possible the use of drilling mud in either conventional drive sample or undisturbed sample borings. The lighter or drill barge can rise and fall with the tide. Rough shop or ground swells do not affect the operations and drilling can be aclcomplished with no more difliculty than that experienced on a regular land boring site.

It is a primary object of this invention to provide an apparatus which will eliminate the problem of adding and taking off pilot casing to compensate for tidal fluctuations during a sub-aqueous drilling operation.

Another object of this invention is to provide a conductor sleeve and packing gland in reciprocating contact with pilot casing for performing sub aqueous drilling with drilling mud.

'Anotherobject of this invention is to provide an apparatus for. performing sub-aqueous drilling from a floating plant which permits the taking of sample borings without adding or taking off drill casing to compensate for tidal fluctuation of the floating plant.

Another object of this invention is to provide a floating sealed gland means and mud lubricating means with-in a conductor casing carried by a floating drilling platform and pilot casing secured in the earth to follow the subaqueous drilling operation of a drilling bit.

The foregoing and other objects and advantages of the invention will appear more fully hereinafter from a consideration of the detailed description which follows, taken together with the accompanying drawings. It is to be expressly understood, however, that the drawings are for the purpose of illustration and description only, and are not intended as a definition of the limits of the invention.

FIG. 1 discloses the complete assembly of the drilling apparatus of the invention mounted in cantilever position overhanging one end of a supporting floating platform;

FIG. 2 illustrates different tidal levels of the floating platform of the invention with pilot casing and packing gland assembled and mounted in position for drilling;

'FIG. 3 is a partial sectional view of the pilot casing and mud pit of FIG. 2;

FIG. 4 is an enlarged view partly in section of the paclaing gland;

FIG. 5 is a perspective view of the mud pit; and

FIG. 6 is an exploded view of the mud pit flange, rubber gasket and conductor casing before being bolted in sealed relationship as an assembly to the bot-tom opening of the mud pit.

In all figures of the drawings, similar reference characters indicate like parts.

Referring to FIGS. 1 and 2, floating barge or platform 8 carries an overhanging cantilever platform 9 on which is mounted drilling derrick 1, drilling means 10, associated pumping means 20, mud pit means 40 and conductor casing means 56. Pilot casing 66 is supported in the surface of a marine land and telescopes within conductor casing means 56 and carries packing gland means 22 as a variably positioned floating seal means between the two casings 56 and 66 as barge means 8 varies in levels of position due to tide fluctuations. Drill bit 31 telescopes Within pilot casing 66 and terminates at its distal end in drilling head 71 as shown in FIGS. 1 and 2.

FIG. 3 discloses the sectional structure of mud pit 40 mounted in platform 9 and the connection of mud pit 40 by bolt means 11, flange means 12, gasket means 13 with the screwed end of conductor tubing 56. Tubing 56 concentrically telescopes over pilot tubing 66 which carries packing gland 22 which is in sealable contact with conductor tubing 56 during the drilling operation. Fluid mud acts as the lubricating means for gland 22 during the drilling operation and fluctuating of the levels of barge 8 between high and low tides. Mud pit 40 shown in sectional view shows the relative positions of screen member 43 and bafile member 46.

FIG. 4 discloses the structural arrangement of the mounting of gland means 22 on pilot casing 66. Gland packing 22 is wrapped on pilot casing 66 and held in place by welded bead ring means 23 and 28 and ring means 240 secured by bolt means 24, as shown. Packing means 22 may be of flexible plastic tubing or other desired material suitable for either fresh water or salt water environment.

FIG. 5 discloses the structural arrangement of mud pit 40 comprising flange support means 42, reinforcing members 47, handle means 45, sediment screen means 43 and baffle means 46.

The method and procedure which makes this invention possible may be described as follows:

A lighter, barge or deck scow 8 with a cantilever platform 9 erected on its bow is shown in FIGS. 1, 2 and 3. The barge is anchored at the boring site. A steel mud pit 40 is lowered into a well in the cantilever drill platform 9, flush with the platform and the core drill 31 is moved into position over the well in the mud pit. Flush-coupled pilot casing 66 is then lowered through the well in the mud pit to the harbor bottom. The pilot casing 66, as shown in FIGS. 1 and 2, is driven into the bottom to a depth suflicient to allow the overburden to support the casing in an upright position. A diamond casing bit may be screwed u) onto the outside of the casing to facilitate the penetration of the overburden. 'Either conventional or undistrubed sampling can then commence using regular drill procedure. 7

Drive sampling or undistrubed sampling is done in' advance of' the pilot casing, until the casing reaches a point" 15 to 20 feet below the harbor bottom. The depth below a the harbor bottom at which the advance of the pilot cas ing can be stopped is dependent on the type of materials encountered at the particularsite. Fifteen to twenty feet is considered suflicient in most marine soil. 7

A' packing gland 22 made up of a section of flush coupled casing 66, weldments23 and 28, two pieces of flexible plastic tubing 26 and 27 fastened to the casing by ring 7 means 24a with bolts 24 approximately as shown in FIG; 4, and the area of gland 22 between the two tubing rings 24a or stops are wrapped with soft braided nylon 25:01 suitablepacking to make up the packing gland 22. The packing gland is then screwed to the top of the string of pilot casing-66. The packing gland is always-placed on the pilot casing just at the, water surface at low tide.

The mud pit flange 12, FIG. 6, is then screwed to the top of the steel conductor sleeve, the inside of the conductor sleeve is well greased and the rubber gasket'placed over the well 42:: of the mud pit. The conductor sleeve is then lowered through well 42a in the mud pit and over the packing gland on the pilot casing 66, and the con-- ductor sleeve flange 12 is bolted by gasket 13 firmly to the bottomtreinforcement 42 of the mud pit 40. The length of the conductor sleeve will vary with the location of the job site, but a ruleto follow is that. the conductor sleeve should be a minimum of five feetllongerthan the differential between low and high tidefat-the particular work location. i i

A salt water or fresh water drilling mud (depending and maintaining casing.

a 4 alarge inventory of'large diameter drill i It is to be understood that this invention is not limited to the particular method, structural components and arrangement thereof that'have been submitted herewith for the purpose of illustration, but may encompass further "support anchored'on a body 'of water subject to tidal fluctuations andabove a point on the'marine bottom, a

a drill prime mover mounted on said support, and an openon the location of the work site) is then mixed with water in the mud pit to the proper consistency.- The lighter or deck scow now can rise. and fall with the tide-and rough j water chop, ground swells or wash caused by passing ships without afiecting the drilling operations. The conductor sleeve or casing '56 slides up and down over the pilot cas- 6 ring in said support in proximity to said prime mover adapted to allow passage of a drill string through said support; the improvement which comprises a water level compensating drill. casing assembly said assembly comprising;

(a) hollow conductor casing means mounted'in said opening and depending from said support for a dis tance greater than the tidal variation in water level and less than the lowltide depth of the body of water; ,(b) a hollow pilot casing having an upper end and a lower end,'said lowerend being embedded vertically in the marine bottom and said'upper end being in telescopic engagement with said conductor casing; (c) flexible sealing gland means mounted on said pilot casing adjacent the upper. end thereof, said gland means, forming asliding seal between said pilot casing and said conductor casing; and V (dlmeans for supplying drilling mud to said gland means comprising a mud pit, said mud pit being provided with an opening adapted to permit the passage of said drill string, said opening being superimposed on the opening-Yin saidfloating support and. means connectingsaid conductor casing to said mud pit, the interior of saidconductor casing being maintained in fluid communicating relationship. with the interior .1 of said mud pit. a a q 2. The apparatus ofjclaim .1 further comprising pump. means, the suction side of said pump being in fluid com- .munication with said mud pit and the pressure side of said Drilling and sampling can then be resumed throughthe pilot casing and below in the uncased hole as shown in FIG. 2, until the required depth is reached. On reaching the final depth in overburden drilling, and bedrock must be cored, conventional size flush coupledcasing can be lowered through the conductor sleeve 56, pilot casing 66 and the uncased portion of :the boring to the top of bed- 'pump being adapted for connection to the upper end of said drill string, 6

I 3.;The apparatus ofxclaim 1 wherein said drill-string is a hollow and extends from a point within the marine bottom to'a pointabove the prime mover, being contained within the pilot casin'g'means and conductor casing means for the coextensive'length of the drill string; the 'upper end of said drill st'ring being connected in fluid communicating rela- 'tionship' to the pressure side of said pump.

rock and coring by means 31 or other suitable meanscan be done in the conventional manner. 'After the final depth has been reached'in bedrock, the flush coupled casing is removed, the drilling mud is pumped'fromfthe mud. pit 40 into drums for use on thenext, boring or disposed of by' pumping over the. side. of the lighten The conductor 4 sleeve is removed from the mud pit, the packing gland 22 removed from the flush coupled pilotcasing66, and'the short string ofpilot casing is removed using conventional:

machines, plus .the necessary equipmentneeded.withlarge,

4. The apparatus of claimglwhereinsaid flexible sealing gland means comprisesisoftjbraidednylon.

I References Citedthe Examiner L 1' UNITED STATES PATENTS u 1,517,556 12/24 Grant' s. -40 "1,766,628 6/30". Grant i 17s 10 1,829,304; 10/31 sc hroeder 175 10 7 1,862,260 6/32 Edmunds; 1 75 216x ;i1,s67,030 7/32 Roberts 175-9 1,870,725 8/32,Grant '175 10 2,571,247 10/51 Huebotter" 175-66 X 2,606,003; 8/52; McNei1l 2 175-4 heavy equipment and eliminates the costof purchasing I Primary Exmmner, 

1. IN A SUBAQUEOUS DRILLING RIG COMPRISING A FLOATING SUPPORT ANCHORED ON A BODY OF WATER SUBJECT TO TIDAL FLUCTUATIONS AND ABOVE A POINT ON THE MARINE BOTTOM, A DRILL PRIME MOVER MOUNTED ON SAID SUPPORT, AND AN OPENING IN SAID SUPPORT IN PROXIMITY TO SAID PRIME MOVER ADAPTED TO ALLOW PASSAGE OF A DRILL STRING THROUGH SAID SUPPORT; THE IMPROVEMENT WHICH COMPRISES A WATER LEVEL COMPENSATING DRILL CASING ASSEMBLING SAID ASSEMBLY COMPRISING: (A) HOLLOW CONDUCTOR CASING MEANS MOUNTED IN SAID OPENING AND DEPENDING FROM SAID SUPPORT FOR A DISTANCE GREATER THAN THE TIDAL VARIATION IN WATER LEVEL AND LESS THAN THE LOW TIDE DEPTH OF THE BODY OF WATER; (B) A HOLLOW PILOT CASING HAVING AN UPPER END AND A LOWER END, SAID LOWER END BEING EMBEDDED VERTICALLY IN THE MARINE BOTTOM AND SAID UPPER END BEING IN TELESCOPIC ENGAGEMENT WITH SAID CONDUCTOR CASING; (C) FLEXIBLE SEALING GLAND MEANS MOUNTED ON SAID PILOT CASING ADJACENT THE UPPER END THEREOF, SAID GLAND MEANS FORMING A SLIDING SEAL BETWEEN SAID PILOT CASING AND SAID CONDUCTOR CASING; AND (D) MEANS FOR SUPPLYING DRILLING MUD TO SAID GLAND MEANS COMPRISING A MUD PIT, SAID MUD PIT BEING PROVIDED WIH AN OPENING ADAPTED TO PERMIT THE PASSAGE OF SAID DRILL STRING, SAID OPENING BEING SUPERIMPOSED ON THE OPENING IN SAID FLOATING SUPPORT AND MEANS CONNECTING SAID CONDUCTOR CASING TO SAID MUD PIT, THE INTERIOR OF SAID CONDUCTOR CASING BEING MAINTAINED IN FLUID COMMUNICATING RELATIONSHIP WITH THE INTERIOR OF SAID MUD PIT. 